Pulleys such as drive pulleys (both front-side and back-side), idler pulleys, and tensioner pulleys may be used in a vehicle. Specifically, these pulleys may be used to drive or tension a belt of a drive system. The belt drive system may include a driver pulley and one or more idler pulleys, as well as an endless belt. The pulleys may each include a pulley shell or body having a belt-engaging surface. The endless belt is trained around the belt-engaging surface of each pulley shell.
Each pulley may also include one or more bearings that may be located within a bore of the pulley shell. Sometimes contaminants such as, for example, dust, sand, salt or mud may enter the bearings. These contaminants may increase wear and reduce the life of the bearing. Thus, a dust cap or cover may be provided to substantially prevent contaminants from entering the bore of the pulley body. For example, some types of dust caps may be constructed of plastic. However, these types of plastic dust caps typically have cutouts or other openings that allow dirt and other contaminants to enter the bore of the bearing shell.
Some other types of dust covers currently available may be constructed of a metallic material, such as steel. These types of metallic dust caps substantially prevent the contaminants from entering the bore of the pulley body. However, metallic dust caps may require a relatively high installation force, making these types of dust caps difficult to install. Moreover, these types of metallic dust caps may sometimes damage or puncture the bearing race located within the pulley body during the removal process. Finally, metallic dust caps are typically destroyed when removed from the pulley body.
Other types of dust caps may have a metallic body and an over-molded layer of rubber to act as a seal barrier. These over-molded types of dust caps may be easier to install when compared to a metallic dust cap without the over-molded layer of rubber. However, these over-molded dust caps also have drawbacks as well. For example, the over-molded dust caps are not reusable. Specifically, these over-molded dust caps include a central, rubber portion that is punctured during removal of the over-molded dust cap from the pulley body. Moreover, these over-molded dust caps may be easily damaged during shipping. Thus, the over-molded dust cap typically needs to be shipped separately from the pulley body. Therefore, there exists a need for an improved dust cap for a pulley assembly that overcomes the above-mentioned drawbacks.